D-Star is using the AMBE2020 vocoder technology and not AMBE+2.r0f wrote:I'd like to see Motorola offer APCO-25 phase II as a host/dsp upgrade in older ASTRO tier products when it's out. The specs call for two-slot TDMA and the AMBE (AMBE+2?) vocoder.ka8ypy wrote:Right now it is Amateur only, but apparently the Japanese Govt is looking into using it as their form of P25 and making more robust.r0f wrote:I thought it was some big fancy commercial standard used in Asia?tvsjr wrote:DSTAR is for amateur use - no encryption capabilities.
If you think about it, it's just another vocoder/dsp combination.
Upgrade the ROS to recognize encryption, add the baord, flip the switch and you are there.
Not sure if the hardware can handle TDMA, but I'm fairly confident it could. So long as the T/R switching is fast enough for TDMA...what's the big deal?
People will be pissed if M makes everyone dump current ASTRO25 products (XTS/XTL 5000, 2500, etc) to buy some new phase II crap![]()
AMBE+2 does sound quite good. I've used it with iDEN handsets--but it has one major flaw. Certain background noise (specifc audio frequencies at specific amplitudes) completely drown out the desired audio frequencies going into the vocoder. It's almost as if you're muted.
This is one of the main reasons why Nextel/Telus dumped AMBE+2 (The new "6:1" vocoder) out of their products. Car noise mutes your voice traffic!
I haven't read up on them so I'm not sure what the difference is.
On a side note...ICOMs D-Star expansion board for the hammy portables and the P25 expansion board for the commercial portables "appear" to be of the same layout and size. I wonder how hard it would be to hax0r the D-Star ROS and put a P25 board in a 91D and have P25 hammy rig???
Just thinking waaayyyy outside the box.